Bumping gaia.json for 3 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/1ff57d77a69f
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Revert "Bug 1047143 - close aps entering task-manager, exitToApp to open/restore"

This reverts commit 1d9a8cf867f281d7ab22402f246bac48d0980c33.

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https://hg.mozilla.org/integration/gaia-central/rev/38c61b71e905
Author: Ben Francis <ben@tola.me.uk>
Desc: Merge pull request #23285 from benfrancis/1054979

Bug 1054979 - Do not show overflow menu for apps r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/a4acf83a64b1
Author: Ben Francis <ben@tola.me.uk>
Desc: Bug 1054979 - Do not show overflow menu for apps
Bumping manifests a=b2g-bump